Unlocking Pre-1850 Instrumental Meteorological Records: A Global Inventory

Abstract

Instrumental meteorological measurements from periods prior to the start of national weather services are designated “early instrumental data.” They have played an important role in climate research as they allow daily to decadal variability and changes of temperature, pressure, and precipitation, including extremes, to be addressed. Early instrumental data can also help place twenty-first century climatic changes into a historical context such as defining preindustrial climate and its variability. Until recently, the focus was on long, high-quality series, while the large number of shorter series (which together also cover long periods) received little to no attention. The shift in climate and climate impact research from mean climate characteristics toward weather variability and extremes, as well as the success of historical reanalyses that make use of short series, generates a need for locating and exploring further early instrumental measurements. However, information on early instrumental series has never been electronically compiled on a global scale. Here we attempt a worldwide compilation of metadata on early instrumental meteorological records prior to 1850 (1890 for Africa and the Arctic). Our global inventory comprises information on several thousand records, about half of which have not yet been digitized (not even as monthly means), and only approximately 20% of which have made it to global repositories. The inventory will help to prioritize data rescue efforts and can be used to analyze the potential feasibility of historical weather data products. The inventory will be maintained as a living document and is a first, critical, step toward the systematic rescue and reevaluation of these highly valuable early records. Additions to the inventory are welcome.

Synthetic Weather Diaries: Concept and Application to Swiss Weather in 1816

“…In a recent project we have uncovered (Pfister et al, 2019) and digitized (Brugnara et al, 2020) many more instrumental series for Switzerland back to the early 18th century, such that we now have ten series for 1816. This effort was part of a global effort to uncover more historical instrumental data (Brönnimann et al, 2019b), a lot of which is currently being digitized. With these data, more accurate reconstructions will be produced in the future.…”

Early instrumental meteorological observations in Switzerland: 1708–1873

“…Past meteorological observations are fundamental to understanding climate variability. While recent variability dominated by anthropogenic warming has been extensively studied (Stocker et al, 2014), less is known about the previous centuries, a period characterised by large regional climate oscillations related to natural forcings (Brönnimann et al, 2019b;Neukom et al, 2019).…”

Recovering Climate Data from Documentary Sources: A Study on the Climate in the South of Spain from 1792 to 1808

“…Although the objective of historical climatology is to reconstruct long and continuous data series which overlap with modern instrumental series, in order to achieve proper calibration and validation [6], the value of short series is now recognized [7]. These generate useful reconstructions of particular years (e.g., the "year without a summer" of 1816), contributing to a greater understanding of extreme events, and of processes such as the transition between different climatic periods, the climatic influence of volcanic eruptions, and intra-annual and interdecadal variability, as well as connecting climate data with their social impacts and responses.…”